Subscriber identification management broker for fixed/mobile networks

ABSTRACT

The present invention relates to a method for managing the automatic provision of a subscriber network identifier from a central network server to a subscribed communication device, the method comprising receiving notification at the central server relating to a change in the current location for the subscribed device, and determining from the notification whether a new subscriber network identifier is to be provisioned from the central server. The method further comprises selecting a subscriber network identifier on the basis of the current location, if the determining step has determined that a new subscriber network identifier is to be provisioned, and outputting the selected subscriber network identifier for transmission to the subscribed device. The present invention also relates to managing the automatic connection of a subscribed communication device to a network, where a preferred network and preferred subscriber network identifier may be used.

FIELD OF THE INVENTION

The invention relates to the management of subscriber identification incommunication networks. Specifically, the invention has particularapplication in the management of identities for users who are customersof one or more home networks while they roam between multiple visitednetworks. In one embodiment, the invention keeps track of thesubscriber's network identifiers and can switch between practicalidentifiers without losing track of the primary customer identity. Theprimary customer identity is usually a unique human being but can be amachine or sometimes a company entity such as a department. Theidentifiers are commonly the customers IMSI (International MobileSubscriber Identity) that resides on a SIM (Subscriber Identity Module)or their telephone number MSISDN (Mobile Subscriber Integrated ServicesDigital Network Number) or other important identities such as MAC (MediaAccess Control) address, IP address, email address and IMEI(International Mobile Equipment Identity).

BACKGROUND ART

The three most commonly used networks in the world are The Internet, theMobile Network and the Fixed Telephony Network and since these networksare essentially linked by a variety of gateways, they form the largestsingle ‘machine’ on the planet. Subscribers roam on these networks andconnect at a variety of points using credentials. These credentials areeither stored in Smartcards such as SIMs, on the devices themselves orin the subscribers' head as ‘passwords’. When a subscriber moves to anew portion of the network they must first identify themselves to thatnetwork and then gain access to that network using an authenticationmechanism.

Patent Tagg WO 02/057869 described a method for users to connect todifferent portions of the Internet through a form of co-operativenetworking. This invention relates to a network mediated method forconnecting to predominantly Mobile Networks.

In the GSM (Global System for Mobile communication) authentication isperformed using a SIM inserted into the mobile communications device.This manages the connection to the network and contains the networksubscriber keys. There are two types of authentication—homeauthentication and roaming authentication. Home authentication isstraightforward and simply requires the exchange of a key with the homenetwork to prove the subscribed user's identity. When the subscribeduser is connected to the home network it is relatively straightforwardto obtain the key, check it against the central database and then grantthe subscribed user access to that network while keeping track of theirusage for billing or credit management purposes. Typically, customersregister to a network in a home location such as a country, state orregion. This home location holds the primary record of that customer(subscribed user) and maintains the billing relationship with them. Thehome location usually maintains a record of the person's actual identityto allow for law enforcement activities, post pay billing and the like.In the case where the communications device is connected to a foreignnetwork this process is more complex and is referred to as roaming.

‘Roaming’ refers to extending the connectivity of a service to alocation that is different from a home location. When a mobilecommunications device, such as a mobile telephone, travels with a useroutside of their home operator coverage area—‘territory’—the device canstill access services using roaming mechanisms/services. However, thereare a growing number of people who live in more than one home and, ofcourse, machines such as airplanes and cars don't have a ‘home’ in thehuman sense of the word.

There are a growing number of internationally mobile people who spendsignificant time in more than one country. The International AirTransport Association (IATA) projects that by 2011 global airlines willbe handling 2.75 billion passengers per year (up by 620 million from2006). As a result of the number of internationally mobile people, it isexpected that the number of people relying on mobile phones and similarmobile communications devices will increase accordingly. InformaTelecoms & Media statistics show international roaming significantlyincreasing, with European outbound roamers expected to increase from 131m to 520 m (+397%) by 2010. Additionally significant growth is occurringin machine to machine communication where a SIM may be used for trackingconsignments and merchantable goods and assets.

Users are poorly served by current systems, which were designed beforethe surge in international travel and are designed to handle customerswho typically lived in one home and who very infrequently travelled awayfrom that home. Users of cellular radio telephone services are familiarwith the roaming surcharges levied for usage of a terminal device,typically a mobile phone, in a foreign network. In this sense a foreignnetwork simply means a network other than the home network that the useroriginally subscribed to. Even the name ‘roaming surcharge’ belies theoriginal network design which was for exceptional behaviour. However,roaming is now extremely common.

There are few options available to users when travelling to a foreigncountry which help reduce these surcharges:—

One option for a user is to purchase a plurality of additional pre-paysubscriber identification modules (SIMs), one for each territory whichthe user visits. A SIM is a plastic card with embedded electroniccircuitry, which has a unique serial number and a unique internationalnumber for the mobile user (IMSI). The SIM enables communication betweenthe mobile device and available cellular networks. Therefore, bypurchasing a plurality of different SIMs,—one for each territory—theuser is able to replace the original SIM with an appropriate SIM for theterritory being visited. In this way, the mobile device appears to be asubscriber on the foreign network, which means the user can make andreceive calls or use data services without incurring roaming surcharges.

This option has many disadvantages:

-   -   the user must purchase and carry around a plurality of different        SIM cards;    -   the user must ensure that there is sufficient credit in the        accounts linked with each SIM card. Furthermore, it is not        desirable to have unused credit on a number of different        networks, as this credit may be wasted without being redeemed;    -   The act of maintaining a plurality of different SIM accounts is        cumbersome and time consuming, involving considerable user        interaction;    -   When the Subscriber swaps SIM their mobile number changes this        means they are no longer reachable on their normally used        number. Further if they make an outbound call their Caller Line        Identifier (CLI) will be a new one and therefore unknown to the        receiver. This may result in the called party refusing to answer        that call as the do not recognise the caller.    -   Law enforcement agencies are frustrated in their endeavours to        keep track of undesirable people as they effectively have to        keep track of multiple copies of the same person.

Another option to reduce roaming charges is to use a service, such asthe one described in Brunnekreef WO2006002951, where the user (or anapplication) on the mobile phone can pre-pend a (sometimes hidden)telephone number of an intermediate service that will accept the user'scall, remove the pre-pended information and call the desired destinationnumber. The caller then drops the call automatically and awaits acall-back. The intermediate service calls the user back to complete theconnection, and this may give the user better calling rates than normalroaming surcharges. This has the disadvantage of introducing a delay inthe communication channel while the user is trying to contact anotherparty. Furthermore, the user gets a very poor user experience due tohandset software compatibility issues: depending on the model of themobile phone, the phone may appear to ‘do nothing’ until it gets thecall back, strange messages such as ‘call failed’ or ‘call blocked’ mayappear or the service may not work at all.

Multi-IMSI SIMs are available that offer the capability of beingpre-programmed with a plurality of mobile subscriber data sets. The datasets are sometimes incorrectly referred to as IMSIs, hence the name‘multi-IMSI SIM’, but are actually data sets which each comprise aninternational mobile subscriber identity (IMSI) and othernetwork-related data.

These SIMS have processing capability and an algorithm to present thecorrect set of data to the phone based on the location of that phone.This allows the phone to present as a ‘local’ subscriber to the networkin question. The problems associated with this algorithmic systeminclude:

-   -   When a SIM is pre-programmed with fixed set of IMSIs, new SIMs        need to be issued if additional IMSIs become available (likewise        for deletion). Therefore, the physical management of the SIMs is        very complex.    -   SIMs contain a preference table which list networks for which a        suitable IMSI is available. These lists of preferences can        change over time and the SIM will rapidly become out-of-date        with respect to the reality of the network. This could result in        roaming charges which are less favourable for the user.    -   While this option may provide a means to originate mobile calls        at a local rate each network is independent of the other and the        subscriber effectively becomes a different person on each        network. In order for the subscriber to remain in contact with        people from their home network the subscriber must either (i)        forward calls from their home country telephone service to their        current visited country's telephone service, (ii) inform their        expected callers of their new number, or (iii) frequently check        voicemail and missed calls in order to communicate with callers.        This again is cumbersome and time consuming for the user.

Many fixed format Dual and Multiple IMSI SIM systems have been sold bycompanies such a as VeriSign™, Gemalto™ and these are described invarious patent applications such as Cammileri (WO2007102003), Stadelmann(WO9955107), Salomon (WO0221872), Bongers (WO0049820). In such systems,a piece of software runs in the SIM or on the handset or a separateelectronic module and makes decisions as to which IMSI to use given thelocation and available networks. Such systems are sometimes calledSmartSIMs, but in fact this is a misnomer as all SIMs are smart andcontain a microprocessor and memory to run network selection andauthentication programs. In addition to the physical problems of SIMmanagement described above, there is a range of more subtle operationalproblems inherent in using a SIM algorithm and a table of IMSIs toeffect a roaming solution:

-   -   One problem is that the algorithm must run in conjunction with        information obtained from the handset and although theoretically        all handsets conform with certain operating standards, in        practice the implementation of such algorithms are highly        incompatible. Therefore, SIM algorithm systems often fail to        operate correctly in common handset models. These failures        include:        -   Random crashes;        -   Simple failure to perform the function; and        -   User messages that appear to make no sense.    -   In addition, the SIM algorithm often has a lack of information        about the network in which it runs and this can cause it to        continuously hunt for an optimum network. During this time the        handset may not reliably make and receive calls and the handset        runs at full power, which can rapidly drain the battery.    -   If the algorithm pre-pends an access number this access number        cannot be practically modified on a call by call basis and so        call routing will not be optimized.    -   The SIM does not have enough knowledge of the network geography        and current commercial status to choose the best network.    -   Such SIMs are essentially a fire and forget system. If the SIM        locks onto the wrong network due to either a change in the        network or a bug in the SIM, it may be lost for ever to the home        network.    -   If the SIM connects to a network for which pre-pay control is        not available then the SIM may be locked into a state where        unlimited charges are permitted.    -   IMSI swapping to a foreign network renders the users normal        value added services inoperable as the home network is now blind        to the user. Services such as short codes, top-up numbers,        voicemail and other convenience services no longer work in the        expected way.

Another problem travellers experience as they travel near country orregion borders is that mobile phones may inadvertently attach to aforeign network, even though they may be physically in a home territory.Under normal operation, once a handset (i.e. a mobile phone) is attachedto a network, it remains attached to it until signal is lost or if thesubscriber manually disconnects. As a result, the user is charged highroaming charges for an extended period even if though they werephysically in their home territory. In some regions such as Canada, USAand India where there is national roaming this effect can lead toaccidentally high bills even when the customer is not travelling at all.

SUMMARY OF INVENTION

According to a first aspect of the present invention there is provided amethod for managing the automatic provision of a subscriber networkidentifier from a central network server to a subscribed communicationdevice, the method comprising receiving notification at the centralserver relating to a change in the current location for the subscribeddevice, determining from the notification whether a new subscribernetwork identifier is to be provisioned from the central server,selecting a subscriber network identifier on the basis of the currentlocation, if the determining step has determined that a new subscribernetwork identifier is to be provisioned, and outputting the selectedsubscriber network identifier for transmission to the subscribed device.

Conveniently, the subscriber network identifier is an InternationalMobile Subscriber Identity (IMSI). Preferably, the IMSI is packaged withother data such as security keys and routing information and is storedas a data record on a Subscriber Identity Module (SIM) within thesubscribed communications device.

The present invention advantageously manages a multiplicity of IMSIs ona single SIM in use in one handset and can dynamically retrieve a localIMSI from the host portion of the system if a suitable one is notalready on the handset. It also manages the telephone numbers associatedwith a given subscriber allocated with multiple IMSIs, the networkconnection preference tables, the routing of calls, subscriber billingand credit management. We shall refer to this inventive concept as the‘IMSI Broker’, which is typically incorporated into a typical MNO, MVNOor MVNE architecture.

Using the present invention advantageously enables a mobile phone user,subscribed to the service or network providing the service, to roam fromnetwork to network and to be automatically configured and connected toroamed-to networks as a local user. This effectively eliminates roamingcharges and therefore reduces the cost of mobile telephone calls anddata usage to much lower levels than was previously practicallypossible.

It is possible to identify the roamed-to network using the MobileCountry Code (MCC) and Mobile Network Code (MNC) (as defined by ITU-TRecommendation E.212)). Therefore, by performing a lookup in the HLRdatabase it is possible to determine if a subscriber has already beenallocated an IMSI for use in the detected network.

Another advantage is that subscribers do not need to set up new accountsor pre-pay to multiple network operators as the system is capable ofmerging all the billing relationships into one single account.

This present invention provides the ability for a single person ormachine to be allowed to have multiple network homes while maintaining asingle customer record, billing relationship and unique binding to theirpersonal or machine identity.

Preferably, the receiving step comprises receiving a notification froman HLR scanner, the HLR scanner being arranged to detect a locationupdate message received by a Home Location Register (HLR) to which thesubscribed device is subscribed, the location update messagecorresponding to the change in current location of the subscribeddevice.

Advantageously, the HLR always knows under which IMSI a customer(subscribed user) is attached to the network and takes care that themapping of the different numbers a customer is using happens correctly.A customer can receive calls and text messages on each of his/hernumbers wherever he/she is.

In an embodiment, the HLR is not associated with a specific physicalnetwork infrastructure for radio communication with subscribed devices.In this case, there is no concept of a home network and all physicalradio networks have equal status in the hierarchy. The effect is thatall customer IMSIs can be treated equally and any IMSI can be selectedas a master IMSI or all IMSI can be peers of each other. This contrastswith many existing design patterns where one IMSI is the home/masterIMSI and must always be returned to from time to time for the purposesof updating settings, resolving billing issues and determining customerownership in a KYC solution. A key benefit of having no singlemaster/home IMSI is that the system can be set in a multi-home modewhere any IMSI can be used for the above purposes. Alternatively allIMSI can be peers and there is no master IMSI whatsoever. In thisscenario when a device loses contact with its base it will search allIMSIs in order to re-contact the HLR.

In a preferred embodiment, the method facilitates a network server basedcall processor heuristically selecting an telephone number (MSISDN) froma set of telephone numbers assigned to the subscriber. The selection isbased on the number which is most suitable for the called party suchthat the called party can identify the subscriber. This advantageouslyavoids the situation where a call is unanswered because the called partydoes not know who is calling. These invention functions facilitate theuse of one or more numbers on one phone on many GSM networks around theworld in a cost-effective manner.

Optionally, the receiving step comprises receiving a communicationsmessage from the subscribed communications device indicating a change incurrent location.

In a preferred embodiment, the determining step comprises retrieving anIMSI list from the HLR for the subscribed device, the IMSI listcomprising all of the IMSIs which are allocated to the subscribeddevice, and determining if the IMSI list comprises an IMSI which isappropriate for the current location of the subscribed device.

Typically, the selecting step comprises obtaining a local IMSI from anIMSI pool comprising a plurality of IMSIs for different locations, thelocal IMSI being selected from a sub pool of IMSIs suitable for thecurrent location.

Selecting a local IMSI is advantageous as it enables the best possibleIMSI to be provided to avoid roaming charges. In this sense, it ispossible to provide a local, regional IMSI (with national roaming rightsto avoid or minimise the roaming charges for incoming calls.

In other embodiments, the step of determining whether an IMSI isappropriate is based on previously determined preferences for thesubscribed device. These may be based on location or costconsiderations, but also on other criteria such as network compatibilitywith a specific handset, or network performance. The preferences mayeither be set wholly within the IMSI table in the SIM or alternativelythe preferences may be held on the network and the SIM may be instructedas to which IMSI it switches to.

This server instruction to change IMSIs is referred to as a ‘kick’. Thebenefit of using server initiated IMSI switching is that much moreinformation is known to the server about the current state of networks,costs and the location of the user, than is known to the softwarerunning in the SIM. The ability to switch IMSIs under software controlshould be done in conjunction with the understanding that the SIM needsto be able to re-contact the HLR through execution of an emergencyreconnect process as mentioned above in connection with Multi-homing Tobe clear if a SIM is instructed by the network—kicked—onto a differentIMSI and after a period of time (about 5 minutes) is unable to connectit must rescan all its IMSIs in order to reconnect with the HLR.

When the IMSI has been chosen and has connected to the HLR and the HLRconfirms that this is a reliable link either through an activeacknowledgement or simply no objection being raised after a period oftime then the SIM should signal to the device and other applicationsrunning on the SIM that there has been an a change and otherapplications should behave appropriately. For example upon SIM swap anda period of stability of 3 minutes the SIM could signal to all companionapplications on the SIM that the IMSI is now stable and otherapplications could report information or log into system.

Preferably, the outputting step comprises outputting the local IMSI toan OTA module for transmission to the subscribed device.

In a preferred embodiment, the outputting step further comprisesoutputting a set of rules concerning when the local IMSI is to be usedby the subscribed device.

Optionally, the outputting step further comprises outputting acorresponding MSISDN for the selected IMSI. Another advantage is thatthe system can manage the telephone number allocation so that it ispossible to maintain a single telephone number for a subscriber eventhough the usage of multiple IMSIs means that the subscriber is actuallyusing multiple actual telephone numbers.

Preferably, the method further comprises updating the HLR when the localIMSI has been provisioned to the subscribed device.

In a preferred embodiment, the method further comprises obtaining apreferred caller line identification (CLI) from a database containing aplurality of CLIs for the subscribed device; and outputting thepreferred CLI for use in completing communication channel set-up.

When making calls or sending texts, the present invention advantageouslyensures that the called party sees a local number (where available).This lowers the barriers to call back and increases traffic and AverageRevenue Per User (ARPU).

Furthermore, as global travellers and callers originate phone calls toothers around the world, the appearance of local presence is desired inorder to facilitate business marketing as well as national-rate returncalls from that locale.

Use of these approaches allow new customisation possibilities for thecustomer. In embodiments, different supplementary services (such asCLIP, CLIR and call forwarding) may be associated with differentsubscriber network identifiers. This allows a customer to developdifferent service profiles for different subscriber network identifiers.

In some cases, it is desirable to maintain customer identity acrossmultiple subscription network identifiers in communication with thirdparties. This is particularly desirable for access to data services—inembodiments, means are provided to enable access to data servicesconsistently for some or all subscription network identifiers for thesubscribed device. In other areas—such as satisfying Know Your Customerrequirements—it is desirable to provide evidence of a subscriber's setof identities to a third party.

According to a second aspect of the invention there is provided acentral network server for managing the automatic provision of asubscriber network identifier to a subscribed communication device, theserver comprising a receiver arranged to receive notification relatingto a change in the current location for the subscribed device, anidentification checker arranged to determine from the notificationwhether a new subscriber network identifier is to be provisioned fromthe server, an identification updater arranged to select a subscribernetwork identifier on the basis of the current location, if thedetermining step has determined that a new subscriber network identifieris to be provisioned, and an output module arranged to output theselected subscriber network identifier for transmission to thesubscribed device.

According to a third aspect of the invention there is provided a methodof connecting to a preferred network at a communication device, themethod comprising: providing notification to a central server relatingto a change in the current location for the communication device;receiving a subscriber network identifier for a preferred network fromthe central server on the basis of the current location, if the centralserver has determined that the communication device is not connected tothe preferred network; and disconnecting from a current networkconnection and reconnecting to the preferred network using the receivesubscriber network identifier. Thus the central server has so-to-speak‘kicked’ the SIM off one network and onto another.

According to a fourth aspect of the invention there is provided acommunication device comprising: storage means for storing a list ofsubscriber network identifiers; processing means for determining, wherea new network connection is required, which subscriber networkidentifier to use to make the new network connection according toselection rules stored in the storage means; and means to accept updateinformation over a network connection, wherein the communication deviceoperates on received update information to update the list of subscribernetwork identifiers and the selection rules.

Preferably, the communication device is adapted, on receipt of updateinformation, to break an existing network connection and to make a newnetwork connection in accordance with updated selection rules.

According to a fifth aspect of the invention there is provided a methodfor managing the automatic connection of a subscribed communicationdevice to an available network, the method comprising determining acurrent location for the subscribed communication device, retrieving alist of available networks for that current location, selecting apreferred network from the list of available networks, and outputting aninstruction for the subscribed mobile device to connect to the preferrednetwork.

In a preferred embodiment the method further comprises monitoringlocation updates for the subscribed communication device, determining ifcurrent network is preferred network, on the basis of network selectionrules.

Preferably, the method further comprises instructing the subscribedcommunication device to disconnect from current network if determined tobe not the preferred network, instructing the subscribed communicationdevice to reconnect to the preferred network.

In one embodiment, the determining step may comprise determining thecurrent location on the basis of the physical location of the subscribedcommunication device as determined using global positioning systems.

Optionally, the determining step comprises determining the currentlocation on the basis of the one or more of the group comprising:Network Country/Operator ID; GSM (Cellular) Cell ID; WiFi access pointID; and other fixed radio network location identifiers.

In a preferred embodiment, the selecting step comprises selecting apreferred theoretical network from the master list of networks known tobe available in a certain locality of the current location.

In another preferred embodiment, the selecting step comprises selectinga preferred (available) network on the basis of the networks which thesubscribed communication device determines are currently available.

Optionally, the method may be carried out on the subscribedcommunication device, the method further comprising receiving an updatedmaster list of networks from the central server.

The present invention extends selecting a subscriber network identifieraccording to the first aspect on the basis of the preferred network andthe current location as determined according to the third aspect.

Advantageously, the present invention uses various rules to attach,using the most favourable IMSI, to the most favourable network in thearea. In addition, the method recognises when a subscriber is notattached to a preferred network and is able to instruct the subscribedcommunications device to automatically detach from the current networkand to either attach to an available known more favourable network, orseek connection to a known more favourable network.

According to yet another aspect of the present invention there isprovided a method for automatically managing an updatable subscribernetwork identifier (IMSI) in a subscribed communication device, themethod comprising: determining when connecting to a current networkwhether the current subscriber network identifier is local to thecurrent network; replacing the updatable subscriber network identifierwith a stored subscriber network identifier, if the stored subscribernetwork identifier is local to the current network; and disconnectingfrom network; and subsequently reconnecting using the updated updatablesubscriber network identifier.

Preferably, the subscriber network identifier is an IMSI, and the storedsubscriber network identifier is one of a plurality of IMSIs stored on aSIM in the subscribed communication device. The selection of an IMSIfrom the plurality of IMSIs stored on the SIM may be governed by IMSIselection rules which are stored on the SIM or the subscribedcommunication device. The IMSI selection rules may be updated byreceiving an updating message from a central server which is arranged tomanage the provision IMSIs to the subscribed communication device.

Optionally, the subscribed communication device may request a new IMSIto be stored on the SIM if the method determines that the SIM does notcontain an IMSI which is local to the current network.

In a preferred embodiment, one or more of the plurality of IMSIs may beoverwritten if the number of IMSIs stored in the SIM reaches an upperlimit.

Preferably, the method further comprises selecting a preferred networkon the basis of current location. This may be achieved though apreferred network list which is stored within the SIM or on thesubscribed communication device. The preferred network list may beupdated by receiving an updating message from a central server which isarranged to manage the automatic connection of subscribed communicationdevice to preferred networks.

In general, the ability to automatically provision additional IMSIswhich are local to a user's current location is highly advantageous asis means that the user is able to take advantage of lower call rateswithout having to carry and maintain a plurality of different SIMs foreach territory (country, region or network). In some cases, mobilephones are prevented from using multiple SIMs, and so the presentinvention is compatible with those cases.

In addition, the amount of user interaction with the functionality ofthe present invention is far lower than some of the prior arttechniques. The methods described herein may operate without the userbeing made aware of them, and so this is a far improved solution.

In addition, as result of linking several IMSIs to one user, it ispossible for law enforcement agencies to keep track of certainindividuals who may be connected with criminal activities. This linkingmay also be useful in assisting network operators maintain records for‘Know Your Customer’ legal requirement purposes.

As described in detail later, it is possible to update IMSI selectionrules and network selection rules which are stored on the SIM or mobilephone. The updating of such information requires minimal data transfer,and as such, it quick and uses minimal bandwidth. In particular, theability to provision new IMSIs to mobile phones is bandwidth efficientas it may be possible to include all of the data necessary in a singleSMS or a modified SMS. This solution is an improvement on all of theprior art systems described above, which suffer from numerous problemsas listed.

The ability to update SIMs/mobile phones over the air in the manner ofthe present invention has previously not possible because of thequantity of data which is involved. The present inventors have devised amethod which minimises the data transfer in order to facilitate aservice where the mobile device can operate using a suitable IMSI andpreferred network, in order to avoid or reduce roaming charges.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an overview of the communications system in which the presentinvention is operating;

FIG. 2 is a schematic system diagram showing the overall systemarchitecture overlaid with the path (dotted lines) of a IMSIprovisioning event;

FIG. 3 is a process flow diagram showing the OTA provisioning processtriggered by the IMSI broker detecting a handset has entered a newcountry or network;

FIG. 4 is a schematic system diagram showing the signalling pathsrelating to a subscriber location update (LU) and provision of a localIMSI;

FIG. 5 is a functional block diagram of the IMSI Broker of FIG. 2 and aSIM;

FIG. 6 is a signalling diagram showing the typical signalling generatedwhen a subscriber enters a new coverage area for which a new IMSI itprovisioned by the IMSI Broker of FIG. 5;

FIG. 7 is a signalling diagram showing an alternative to FIG. 6, wherethe SIM determines that a suitable local IMSI is already stored on theSIM;

FIG. 8 is a signalling diagram showing typical signalling for CLIsubstitution when a subscribed user is making a call;

FIG. 9 is a signalling diagram similar to FIG. 8 showing a creditmanager and including signalling relating to billing and creditmanagement functions;

FIG. 10 is a simplified flow diagram for a CAMEL callback call set uparrangement;

FIG. 11 is a simplified flow diagram for a USSD callback call set uparrangement;

FIG. 12 is a schematic illustration of two neighbouring countries andcell coverage across the borders of the two countries;

FIG. 13 and FIG. 14 are signalling diagrams relating to the signallingof an incoming call;

FIG. 15 is a map of the world illustrating a method of setting up userpreference rules for incoming call routing on the basis of location,current time, and time-zone;

FIGS. 16A-E illustrates architectures which enable a handset to use acommon set of APNs in embodiments of the invention; and

FIG. 17 is a schematic illustration of the state diagram for a SIM cardin embodiments of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 (Prior Art) is a schematic representation of two cellulartelecommunications networks, one in the UK and one in Italy. In realitythere are many more Mobile Network Operators (MNO), Mobile VirtualNetwork Operators (MVNO) or Mobile Virtual Network Enablers (MVNE), andas such many more cellular telecommunications networks. However, FIG. 1represents only two networks for simplicity.

When a first user makes a call from a first mobile phone 10 in the firstuser's local network, for example, in the UK, to a second user 20 in aforeign network (i.e. Italy), the call is routed through the localnetwork's base station subsystem (BSS) 30 to a local network switchingsubsystem (local-NSS) 32, the call is then routed through the SignalingSystem Number 7 (SS7) 34 network to the foreign network, and through aforeign network switching subsystem (foreign-NSS) 36 to the foreignnetwork's base station subsystem 38. The call is finally routed to thesecond user's mobile phone 20. Calls in the opposite direction arerouted in the same way, through the foreign network's base stationsubsystem, to the foreign network switching subsystem 36, through SS7 34to the local network switching subsystem (local-NSS) 32, on to the localnetwork's base station subsystem (BSS) 30, and finally to the firstmobile phone 10.

The way that the call is routed to the correct recipient is through aplurality of location registers which form part of the networksubsystems. For every user registered in a particular cellulartelecommunications network, there is a record held in that network'sHome Location Register (HLR) 40, 42. The HLR 40,42 is a central databasethat contains details of each mobile phone subscriber that is authorizedto use that particular network.

The HLR stores details of every Subscriber Identity Module (SIM) cardissued by the mobile phone operator (i.e. MNO, MVNO or MVNE). A SIM is aplastic card with embedded electronic circuitry, which is inserted intothe mobile phone. Each SIM has a unique identifier called anInternational Mobile Subscriber Identity (IMSI) which is a primary keyto each HLR record. IMSIs are used in any mobile network thatinterconnects with other networks, including CDMA and EVDO networks aswell as GSM networks.

An IMSI is usually 15 digits long, but there are some exceptions.Typically the first 3 digits are the Mobile Country Code (MCC), followedby the Mobile Network Code (MNC), (either 2 digits (European standard)or 3 digits (North American standard)). The remaining digits contain amobile station identification number (MSIN) within the networks customerbase.

SIMs also comprise one or more MSISDNs, which are the telephone numbersused by mobile phones to make and receive calls. Each MSISDN is also aprimary key to the HLR record.

In summary, there is a relationship between the HLR, MSISDN, IMSI, andthe SIM. The SIM is the physical device which contains a record of theIMSI. The MSISDN is the unique number identifying the mobile phone. TheIMSI is the unique identifier of the user subscribing to the network,and the HLR is the system that maps MSISDNs to IMSIs and vice versa.

The above holds true when a user ‘roams’ away from their home/localnetwork to a foreign network also called a roamed-to network. However,when a mobile phone attempts to connect to a network which is not thehome/local network, the roamed-to network communications with the homenetwork in order to verify whether the mobile phone is authorised to usethe roamed-to network. This communication is possible because there arereciprocal agreements between many of the available network operators.

When a user roams away from their home service and into an area servedby another operator, messages are exchanged over the SS7 network and theroamed-to network operator obtains information from the home network'sHLR and creates a temporary record for the subscriber in its VisitorLocation Register (VLR) 44, 46. The VLR is a database which ismaintained by a network operator (in the same way as the HLR ismaintained). However, the VLR contains temporary information aboutmobile users that are currently located within the service area of (andconnected to the network operator), but who are subscribed with an HLRof a different operator elsewhere. When calls are made from the mobilephone, the VLR is checked for authorisation, and assuming authorisationis permitted, the Mobile Switching Center (MSC) permits tracking of theuse of the mobile phone for billing purposes. The HLR subscriber profile(i.e. which services are allowed) is downloaded to the VLR whensubscribed user registers on (connects to) the network (same for roamingand home network). All call handling and billing related call datarecord (CDR) generation is done by the MSC—the HLR/VLR is not involved.

So using the example in FIG. 1, a user subscribed to a mobile networkoperator in the UK visits Italy. When the user arrives in Italy andturns on the mobile phone, the mobile phone will try to connect to anavailable Italian network operator 36. The Italian network operator canidentify from the IMSI number stored in the SIM card that the user isnot subscribed to the Italian network, and as such, will contact theuser's home network 32 in the UK to verify whether the user isauthorised to use the Italian network.

The VLR 46 updates the HLR 40 in the UK, with location information overSS7 with a Location Update message (LU). The LU message is routed to theHLR(UK) based on the global title translation of the IMSI that iscontained in a Signalling Connection Control Part (SCCP) field of theLU. The HLR(UK) informs the VLR(IT) as to the status of the subscriberand whether service is to be provided in the roamed-to network, i.e. theItalian network. If the user is authorised, the Italian networkgenerates a temporary record for the user in the Italian VLR 46.

As described above, there are problems associated with roaming servicesin that users connected to a roamed-to network incur heavy surchargeswhen making or receiving calls or using data services on their mobilephones. This is true regardless of where the user is calling, or who iscalling the user. In the above example, the user visiting Italy willincur roaming charges when calling local Italian phone numbers as wellas calling phones in the home network in the UK and elsewhere.Similarly, roaming charges will be applied to incoming calls from eitherUK, Italian or other phone numbers.

The prior art methods for reducing these roaming charges are cumbersomeas they require the user to purchase, carry around, and maintain theaccounts of, many different SIM cards, or they require a high degree ofuser interaction in order to utilise one of the services to circumventthese roaming charges. However, as described above there are many knownproblems with these services.

One aspect of the present invention resides in the integration of anadditional central server within a typical cellular telecommunicationsnetwork. The additional central server is able to provide, as required,a plurality of additional IMSIs to a mobile phone, when the mobile phoneis connected to a roamed-to network in another country/region. Theadditional central server is referred to as an IMSI Broker.

In one embodiment of the invention, the IMSI Broker is arranged todetermine whether the SIM card in the mobile phone has an appropriateIMSI for the roamed-to network. The SIM cards required for thisembodiment of the invention are capable of storing a plurality ofalternative IMSIs for different networks, together with associated rulesgoverning when the alternative IMSIs should be used. In this embodiment,the IMSI broker has access to a database store of alternative (new)IMSIs for multiple foreign networks (FNOs) and is arranged to distributethese new IMSIs as necessary to users who are subscribed to a networkcomprising an IMSI broker and, who are roaming across networks.

In one embodiment, each SIM has the capability of storing a plurality ofIMSIs that can be used in a specific territory (country or region) toachieve the best possible calling rates. The SIM also has a set of rulesto drive the selection of the best possible IMSI. Every time a userenters a different territory (mostly a new country, but it could also bea new region within a country), the IMSI Broker will issue the bestpossible IMSI and IMSI selection rules for that territory. The IMSIBroker will send this new IMSI to the SIM via Over The Air (OTA). Thissolution eliminates the need to swap out SIMs when new wholesale networkdeals become available. Subscribers are issued an additional IMSI whenand where available.

Updates and management of the data in the SIM can be achieved over theair interface using any available OTA radio connection. Some examples,include but are not limited to, cellular signalling channels, cellulardata connections, text messaging, WiFi, Bluetooth & WiMAX. A personskilled in the art will appreciate that ‘OTA’ shall include all possibleconnections to the mobile handset and any other method of transferringdata to the handset device such as wired connection to a PC, Infra-Redand so on.

In one embodiment, the SIM may, at the time of manufacture, beprogrammed to include a plurality of IMSIs corresponding to populardestinations. In another embodiment, the SIM may be programmed with aplurality of IMSIs at registration with the network, in accordance withuser selection of countries or territories to which the user expects tovisit in the future. In another embodiment, the SIM may only compriseone IMSI after manufacture and registration, such that all of thenew/alternative IMSIs are delivered from the IMSI Broker as and when theuser visits new countries/territories.

SIMs are evolving continuously, and currently known SIMs may be capableof storing up to 256 different IMSIs in the SIM's memory. This number islikely to increase further. However, regardless of the number of IMSIsthat the SIM is able to hold, other memory constraints may mean that anupper limit is placed on the number of IMSIs to be stored within theSIM. In cases where an upper limit is reached, according to oneembodiment of the present invention, the SIM is able to dynamicallyoverwrite a stored IMSI with a newly obtained IMSI. The decision as towhich IMSI is overwritten can be based on a number of factors, forexample, any unused IMSI may be the first to be overwritten. LikewiseIMSIs that have been used the least, or which have been used lessfrequently may be overwritten before more popular/recently used IMSIs.

The IMSI broker maintains a database of the status of IMSIs distributedto subscribers as they roam and use different networks. In addition, theIMSI Broker is arranged to update the HLR with details of a current IMSIfor each user. This is necessary in order for other parties to contact auser who is using a current IMSI which differs from their original IMSI.

It is an advantage of this embodiment of the present invention that allof the IMSIs and MSISDNs issued to subscribed users can be recorded andattributed to the user. This is advantageous for many reasons in thatlaw enforcement agencies may be able to link call activity from users toone subscribed user account.

In addition, the facility of linking user accounts of differentcountries/regions to one subscribed user is helpful for “Know YourCustomer” (KYC) legal requirements.

In certain countries, there are specific legal requirements relating tohow users may be issued with telephone numbers and according to oneembodiment of the present invention, it is possible for the user to besent additional information (through any suitable communication channel)regarding what steps the user must complete in order to be able tocomplete these legal requirements.

In one embodiment, the present invention is arranged to issue a hiddentelephone number (MSISDN) which is used for call routing purposes to theuser. The user is never made aware of this number and so cannot issue itto other parties, or make use of it for CLI purposes.

In another embodiment, the present invention is arranged to notify theuser of the issued telephone number (MSISDN) so that it can be passed toother parties for CLI purposes. As above, certain countries (for exampleIndia) may require additional steps before subscribed users in theircountry may be given new phone numbers. In one embodiment, the presentinvention notifies the user (for example, by short message service (SMS)also known as text messages) e-mail, or any other suitable communicationmethod) what steps have to be carried out before the telephone numbercan be released to them.

It is to be appreciated that in some cases, the home network may have‘known’ the subscribed user for a considerable time before issuing themwith new IMSIs and MSISDNs in foreign countries, and as such the systemof one embodiment of the present invention, may satisfy the KYCrequirements for certain countries without requiring the additionallegal requirements discussed above.

FIG. 2 shows an overview of the components within a network with anintegrated IMSI Broker 108. In this sense, network need not be limitedto the physical network which is operated by a single network operator.In other words, the term network may be taken to mean a collection ofco-existing networks.

The network communications with the plurality of subscribed mobilephones 101 through the base station subsystem, which comprises a basetransceiver station (BTS), Base station controller (BSC), and a MobileSwitching Centre (MSC).

The base station subsystem communicates with the HLR 111, which in turncommunicates with the IMSI Broker 108 and an Intelligent Network(IN)/Back-office Services system (BSS) module 113. The IN/BSS module hasaccess to a user dB 112 which comprises a record for each usersubscribed to the network. The IN/BSS module 113 is responsible formonitoring the user's usage, i.e. voice calls, SMSs, data usage etc,such that a record is kept for billing purposes. In one embodiment, theIN module 113 is also responsible for ensuring that caller IDinformation, also known as Caller Line Identification (CLI), is storedand provided during calls while roaming, to ensure that there istransparency for the called parties.

The IMSI Broker 108 has access to an IMSI Pool 109, which is a databasecomprising a plurality of available IMSIs for differentterritories/locations. IMSIs by there nature are territory specific.They are both country specific, and may also be region specific incountries (i.e. USA, India) where there may be surcharges for regionalroaming as well as international roaming. An IMSI which is registered onan HLR in one territory will be deemed to be roaming if connected to anetwork/HLR in a different territory. Therefore, for each territory inthe IMSI Pool 109 there is a sub-pool or range of suitable IMSIs whichmay be used. This is described in more detail later.

The network also comprises an OTA module which is arranged to sendupdate messages to mobile phones as necessary. See arrows 107, 104, and110 in FIG. 2. The update messages may include alternative IMSIs and/orrule update messages. This updating mechanism is not limited toprovision of alternative IMSIs or associated rules—it may also be usedto provide other updates to the SIM card (such as new versions ofinstalled software) and also for verification of settings.

The HLR is further arranged to communicate with a plurality of foreignnetworks (operated by foreign network operators FNOs 106). Thecommunication channel between the HLR and foreign networks is throughthe SS7 network 105.

In the arrangement shown in FIG. 2, the home network is shown asincluding a physical networking infrastructure, including MSCs, BSCs andBTSs, adapted to provide a radio signal to a user's mobile phone. Inembodiments of the invention, these elements of a physical networkinfrastructure need not be present. In such a case, the home network maytreat every network to which the user's mobile phone is connected as anFNO. As is discussed below, this can be of assistance in allowing userpreferences and behaviours to be supported without their beingdetermined by the requirements or characteristics of a particularphysical network.

FIG. 3 is a flow diagram showing the steps that are carried out when amobile phone attempts to connect to a foreign network. As shown, when amobile subscriber roams, at step 200 into an area served by anotheroperator, messages are exchanged over the international SS7 network. Theroamed-to operator obtains information from the home network's HLR andcreates a temporary record for the subscriber in its VLR. The VLR thenupdates the HLR with location information over SS7 with a LocationUpdate message (LU). The LU is routed to the HLR based on the globaltitle translation of the IMSI that is contained in the SignallingConnection Control Part (SCCP) field of the LU. The HLR informs the VLRas to the status of the subscriber and whether service is to be providedin the roamed-to network.

The IMSI Broker 108 is able to monitor the HLR log files 150 todetermine, at step 202, if the customer has entered a new country. Ifthe customer has entered a new country, the IMSI Broker 108 according toone embodiment, checks the records for that subscribed user (i.e. theuser records relating to that SIM) to ascertain whether there SIMalready has an IMSI which is suitable for that country.

The IMSI broker 108 verifies that a subscriber to the system has theappropriate IMSI when registering on a GSM network for that particularcountry. If not, the IMSI Broker will update the subscriber's SIM bytriggering, at step 204, the sending of OTA updates with the appropriateIMSI as well as the rules on the SIM that are used by the multi-IMSIapplet on the SIM CPU to select the correct IMSI in a particularcountry. The IMSI Broker records that a new IMSI has been provided, andupdates, at step 206, the user's records in the HLR.

FIG. 4 is a functional diagram of the components within the networkshowing how the IMSI Broker integrates with the network. FIG. 4 showsthe communication paths between the SIM of a mobile phone and thenetwork, including an HLR, IMSI Broker, and OTA module.

The signalling paths generated for a subscriber location update (LU) areshown by the curved arrows in FIG. 4.

A schematic block diagram of the functional components within the IMSIbroker 108 is shown in FIG. 5. As shown, the IMSI Broker 108 comprisesan IMSI updater 500, and IMSI checker 510, and a rules manager 520.

FIG. 5 also comprises a schematic block diagram of the functionalcomponents within the SIM 530. As shown the SIM comprises a current IMSI540, a current MSISDN 542, a SIM application (SIMAPP) 544 for executingfunctional steps on the SIM, and a database 546 of available IMSIs,associated rules, and MSISDNs.

The mobile phone containing the SIM 530 communicates with the visitednetwork over the radio network shown in FIG. 4. The visited network(MSC) determines from that communication, the current IMSI 540, whichthe mobile phone is using, and this points to the HLR (of home network)for the current IMSI 540. In one embodiment, the mapping and routingrules to the Global Title (GT) of the HLR are defined in everyoperator's IR.21. The visited network (MSC/VLR) then communicates withthat HLR over SS7. This is shown by arrow 320 in FIG. 4.

As shown in FIG. 5, an HLR scanner 550 communicates with the HLR 111 andwith the IMSI Broker 108. The HLR scanner 550 is arranged to scan theHLR log files 150 continuously. The IMSI broker 108 receives messagescontaining an Active IMSI (the current IMSI 540) and a Global Title(GTVLR) for every Location Update which is logged in the HLR. For agiven subscriber, the IMSI checker 510 verifies, using a set of rules(IMSI selection rules 560), if the Active IMSI is appropriate for thetarget country. If not, the IMSI updater 500 retrieves an appropriatelocal IMSI from the IMSI pool 109, together with IMSI operationalselection rules, which are executed on the SIM of the mobile phone toensure future selection of the most appropriate IMSI. The term local inthis sense means relating to or local to the user's current location,such that a mobile phone using a local IMSI will appear to the HLR ofthe visited network, as being a subscriber to that network, or being asubscriber to a network in the same territory. As discussed above, it isdesirable to appear to be a locally subscribed device in order to avoidroaming surcharges. Local in this sense may be in relation to aparticular country or region. In some countries (i.e. USA and India)users may be charged for regional roaming A person skilled in the artwill appreciate that where we refer to a best IMSI for a user's currentlocation, the best IMSI may be suitable for the country, region ornetwork which the user is attached to. It is also possible to select thebest IMSI in relation to a preferred network to which the user isinstructed to attach.

In addition, roaming charges may be applied to incoming calls in certaincountries/regions, and these charges can be minimised and even avoidedaltogether by issuing local (regional) IMSIs with national roamingprivileges.

The local IMSI and the IMSI operational selection rules are passed tothe OTA module 103 (arrow 330 in FIG. 4), and then on to an SMS center(SMSC) 104 (arrow 340 in FIG. 4) which is arranged to send the localIMSI and the IMSI operational selection rules to the SIM by SMS message(arrow 350 in FIG. 4). The IMSI updater 500 also records that this IMSIhas been sent to that user in the HLR record for the user (arrow 360 inFIG. 4).

In one embodiment, the IMSI checker 510 is able to determine from thedata record for the user, whether the SIM already contains a suitableIMSI for the target country. If the SIM already has an appropriate IMSI,then the IMSI Broker 108 will not provide a new IMSI. In one embodiment,the IMSI Broker will record that the SIM has an appropriate IMSI, andwill await a further LU message when the SIM connects to the visitednetwork using the appropriate (stored) IMSI. In one embodiment, the IMSIBroker may perform a check routine after an expired time, to check thatthe SIM has correctly changed over to the appropriate IMSI. The IMSIBroker may then send instruction to force the SIM to change IMSI ifnecessary.

The SIM 530 may select an appropriate local IMSI form the storeddatabase of IMSIs 546, on the basis of the rules within the SIM.Alternatively, the SIM may receive a new IMSI from the IMSI Broker 108.Regardless of where the appropriate/new IMSI derives, the SIM isarranged, through an application on the SIM (SIMAPP) 544, to present thenew IMSI to the phone. The phone sends the new IMSI to the visitednetwork, so that the phone appears to be a home subscriber on thevisited network.

Additionally, according to one embodiment, local Mobile SubscriberIntegrated Services Digital Network Numbers (MSISDNs) are also allocatedby the IMSI Broker, configured and activated so that callers can dialthe user's original allocated number (i.e. the phone number of the useron their home network), even though the subscriber is now registered ona different network with a different MSISDN.

This functionality may be illustrated with the help of FIG. 1. User1 ishas a mobile phone registered in the UK. User1 has an original IMSI andan original MSISDN. Without the present invention, when User1 visitsItaly, he is charged roaming charges for making and receiving calls, forsending SMS messages and for using data services. With the presentinvention, User1 has access to a local IMSI so that when User 1 uses hismobile phone, it appears that he is a registered user in Italy, and assuch does not pay roaming charges. In addition, according to oneembodiment of the present invention, User1 also has access to a localMSISDN (i.e. an Italian phone number) such that when people contactUser1 from within Italy, they are charged national call rates ratherthan international call rates. This local MSISDN may be hidden from theusers' points of view, but the call routing is effected as if User1'sphone number (MSISN) is a local number (local MSISDN).

In an example embodiment, the IMSI Broker typically may have thefollowing interfaces (as shown in FIG. 5):

-   -   1. An interface to the HLR Log Scanner on which it receives IMSI        and GTVLR messages for each LU of a system subscriber.    -   2. An interface to the system HLR commands to:        -   a. Retrieve the IMSI list of a subscribed user        -   b. Provision a new IMSI for a subscribed user        -   These commands could be any query protocol. In one            embodiment, this could be achieved using Lightweight            Directory Access Protocol (LDAP).    -   3. An outgoing interface OF to the OTA services through which        Elementary Files (EFs) on the SIM are updated with the IMSI and        other relevant EF data.

FIG. 6 is a signalling diagram showing the typical signalling generatedwhen a subscriber enters a new coverage area, for which a new local IMSIis required. A description of the signals shown in FIG. 6, labelled 1 to10, is provided below.

-   -   1. Handset (mobile terminal—MT) 600 arrives in new coverage area        (i.e. when a user gets off plane in new country). A Location        Update (LU) 602 request is sent from the MT 600 to the visited        Mobile Station Controller (MSC) 604. The LU contains details of        the MT's home network and the MSC determines that the MT is not        subscribed to the network of the MSC 604. As a result, the LU        request 602 is forwarded to the visited Visitor Location        Register (VLR) 46. A person skilled in the art will appreciate        that this is a standard network operation for a roaming handset.    -   2. The LU is then forwarded to the Home Public Land Mobile        Network (HPLMN)/Home Location Register (HLR) 111 of the MT's        home network. The HPLMN is the home network, that the user is        subscribed to. The HPMLN comprises an HLR which contains the        subscribed user's subscription data. The HPLMN may also contain        various service nodes, such as a short message service centre        (SMSC), and a service control point (SCP).        -   a. This LU 602 includes an authorisation request to verify            whether the user has privileges to use the foreign network.            Again, this is a standard network operation for a roaming            handset.    -   3.        -   a. The LU is identified (picked up) by the IMSI broker 108.            The IMSI Broker is arranged to identify whether the MT has            an appropriate IMSI(s) for a preferred visited network(s) in            the new coverage area/locality.        -   b. The HPLMN/HLR 111 also sends a Location Update Accept            (LUA) 604 message back to visited network VLR. The LUA            message contains an indication to the visited network that a            roaming agreement is in place and gives authorisation for            the MT to connect to the visited network and to be able to            make calls and data connections, albeit at roaming rates.            Again, this is a standard network operation for a roaming            handset.    -   4. The visited network registers the MT by sending the LUA to        the MT. The MT is now connected at roaming tariff rates to the        visited network. This is also a standard network operation for a        roaming handset.    -   5. The IMSI Broker 108 determines at Step 3a, that the MT does        not have an appropriate IMSI(s) for a preferred visited        network(s) in the new coverage area/locality, the IMSI Broker        retrieves an appropriate IMSI 606 from the IMSI Pool and passes        the new IMSI(s) data record(s) to the OTA module 103 to be        transmitted to the MT.    -   6. The OTA service transmits the retrieved IMSI data record(s)        to the MT via the visited network. This step uses an appropriate        standard signalling method as available, such standards include        but are not limited to SMS, USSD, IP.    -   7.        -   a. a SIM application (SIMAPP) 544 on the SIM 530 detects new            IMSI data record(s), adds new IMSI(s) to SIM database.        -   b. SIMAPP disconnects MT from network and causes rescan of            available networks.        -   c. SIMAPP detects IMSI match for preferred visited network            and sets appropriate IMSI as current (which may not be the            same as the original visited network)    -   8. MT sends LU to preferred network MSC which is identified as        coming from a home IMSI. (standard network operation)    -   9. Preferred network registers MT with LUA    -   10. MT now registered as local user.

FIG. 6 details the signalling when the IMSI Broker is to provide a newlocal IMSI. However, in one embodiment, as shown in FIG. 7, an applet(SIMAPP) on the SIM in the mobile device is able to check whether theSIM already has access to an IMSI which is local to the current locationof the mobile phone.

The SIMAPP performs a network scan to ascertain a current location forthe mobile phone. Typically, this happens at power on, i.e. aftertravelling and arriving at an airport in another country. But this mayhappen at other times, for example, when travelling across borders, amobile phone may lose the signal of their home network, and attempt tofind another network. When a new network is identified, the SIMAPPchecks to see if there is a local IMSI for that territory (i.e. fornetwork, region or country). The SIMAPP passes the identified local IMSIto the mobile phone which communicates with the visited network toperform a location update.

This location update is very similar to that described above in relationto FIG. 6. However, in this case the IMSI appears to be local to thevisited network, and as such the location update is passed to the MSC &its HLR rather than as shown in FIG. 6 where it is passed to the MSC andits VLR. The local IMSI does include a pointer to the HLR of thesubscribed user's home network. The home network Intelligent Networkcontains information about the subscribed user for CLI and billingpurposes. However, in this case, the charges are not roaming chargesbecause the IMSI is registered with the MSCs HLR and not VLR.

The IMSI Broker is notified of the location update so that the home HLRis aware that the mobile phone is using the appropriate local IMSI asexpected. In one embodiment, the IMSI broker performs a check each timeit receives a location update notification to ascertain whether a newlocal IMSI needs to be sent. And in this case, the IMSI Broker can tellthat the IMSI used for the location update from the mobile phone is alocal IMSI such that another IMSI need not be sent.

As in the case with FIG. 6, at the end of the signalling in FIG. 7, themobile phone is registered as a local user with the visited network.

FIG. 8 is a signalling diagram which shows the typical signalling forCLI substitution when a subscribed user is making a call. FIG. 8comprises Steps 1 to 10, as described below:

-   -   1. The IMSI contains authorisation pointer information such that        when LU takes place on preferred visited network, the LU is        forwarded to home HPLMN/HLR    -   2. The home HPLMN/HLR issues LUA, LUA forwarded to MT and the MT        is now fully authorised.    -   3. The User selects number to call and initiates call on MT;        call setup message sent to MSC & HLR of visited network    -   4. Visited network identifies IMSI as requiring Initial        Detection Point (IDP) trigger to be sent to home HPLMN/HLR; the        IDP trigger sent to home HLR/(HPLMN)    -   5. Home HPLMN/HLR receives IDP trigger;    -   6. IN send message to visited HLR (VPLMN) to indicate INVITE        signalling to be sent to home MSC.    -   7. INVITE sent to home MSC; includes destination number    -   8. The Home MSC retrieves call and CLI details from IN platform        using rules for destination number    -   9. INVITE sent to destination network (here shown as PSTN but        not limited to)    -   10. Call proceeds from MT to destination using CLI.

In one embodiment, the IN may comprise a CLI Selection Controller thatoverrides the CLI with one from the callee's country from the subscribeduser's profile, if one exists.

In one embodiment, CLI Selection Controller is arranged to choose a CLIby:

-   -   1. Receiving a mobile originated phone call from the subscriber        user;    -   2. Determining a set of directory numbers (DNs) available for        use by that subscriber user;    -   3. Evaluating the cost of return call to each of the DNs in step        2;    -   4. Assigning the DN with the least return call cost to be the        CLI for the call; and    -   5. Continuing the call using the assigned CLI.

In one embodiment, the CLI Selection Controller may choose a “TravelCLI” from a pool of telephone numbers which are assigned to thesubscriber user for a brief period, for example 7 days.

In another embodiment, the CLI Selection Controller may choose a CLIbased on a rule indicated in the callers address book for the callee,e.g., Home or Business.

A person skilled in the art will appreciate that the caller ID maycomprise: numeric data; alphanumeric data. Furthermore, the caller IDmay be provided as FSK data, or from an ISDN connection.

In one embodiment, a user is offered a new CLI when they enter asupported county via a text message, and this offer is made via a dataor control channel.

In addition to selecting the most suitable CLI for out going calls, itis necessary to ensure the correct routing of calls to subscribed userswho have a plurality of DNs (MSISDNs). This functionality is ensured asa result of how the numbers are issued. Since the numbers are issued bya particular network operator (MNO, MVNO, or MVNE), the numbers areconsidered as ‘belonging’ to those networks. In one example, calls tothe numbers of subscribed users are routed to the switch of the networkoperator which issued the number. In another example, the calls arerouted to a third party, the Intelligent Network of that third partysends a trigger to the network operator such that the network operatorcan make a decision regarding how the call is routed.

When the call information comes to the network operator (host),operating in accordance with one embodiment of the present invention,the Intelligent Network is able to retrieve details of the recipient,and is able to select the most suitable call route in order to completethe call.

Further details relating to incoming calls are found below in relationto FIGS. 12 to 14. However, it is to be appreciated that the above CLIlogic also applies to SMS not just to calls.

According to one embodiment of the present invention, it is possible forthe Intelligent Network and Back-office services system to aggregate theusage records (Customer Data Records—CDRs) for a user who is/has used aplurality of networks. This information may be presented to the user ina simple to understand single bill or statement as though the subscriberwere using one network only.

This is possible because when the mobile phone is connected to thevisited network using a local IMSI, the IMSI contains a pointer to thehome HLR of the user, and as a result, when the user makes or receivescalls in that visited network, the IN of that network is able to trackthe usage for billing and credit management purposes.

One embodiment of the present invention ensures dynamic allocation ofcalling credit across a plurality of accounts (i.e. accounts for eachIMSI) with a plurality of operators such that a subscriber is onlyrequired to manage a single credit entity.

In one embodiment, the account associated with an IMSI is configured asa pre-paid account. This ensures that more complicated debit or post-payaccounts are not required.

This is an improvement over the option where a user acquires multipleSIMs and pre-loads them with credit for calling in different countriesor networks, which means that the user can end up with several pre-paidtelephone accounts with operators with unused credit.

In one embodiment, the Intelligent Network System ensures thatsufficient credit is dynamically allocated from the user's account/poolto make a given call. In addition, the Intelligent Network System canensure that any unused credit is recovered for allocation to the nextactive account.

A person skilled in the art will appreciate that the allocation ofcredit to accounts and the subsequent recover of unused funds ispossible centrally through the Intelligent Network System. The onlyrequirement in relation to the present invention is that credit isapplied to IMSI accounts for users who have available credit in theiraccount. In some cases, this credit may be pre-paid credit, while inother cases the user may be billed subsequently for services used. Inboth cases the user must have available credit in order for the call tobe made.

The above functionality is highlighted in FIG. 9, which is very similarto FIG. 8, but which now includes the signalling between the homenetwork MSC, the Intelligent Network, and a credit manager. As before,the home network MSC retrieves call and CLI details from IN platformusing rules for destination number. Now at step 9 in FIG. 9, the INplatform requests a credit check for the user to the credit manager. Theuser passes the credit check, and a CREDIT OK signal is passed to theMSC so that the call may be connected. As the call continues, the INplatform requests top-up credit for the IMSI account so that the credit(assuming the user has available credit) does not expire while the callis pending. As shown in FIG. 9 the get call credit transactions mayoccur every 10 seconds are so. In this way, the call is routed using alocal IMSI to get favourable rates, but the IN of the home network cancontinue to add small amounts of credit to the account associated withthe local IMSI. By adding small amounts of credit as necessary, it ispossible to avoid having unnecessary credit in an IMSI account which maybe wasted or used infrequently. As described above, it is also possiblefor the credit manager to remove unused credit from an IMSI account ifnecessary, at the end of a call.

The ability to reconcile customer information relating to billing to allthe separate IMSIs that are used by a particular user is important notonly for user convenience (one bill from one provider, who has beenresponsible for all IMSI provisioning), but also for Know Your Customerlegal requirements. The ability to reconcile these separate identitiesat a single home network with extended knowledge of the user may make iteasier to satisfy Know Your Customer requirements (and, for example, toallow proof that these requirements are satisfied in one country tocontribute towards acceptance of the customer in another). There aresome situations in which the presence of multiple available IMSIs maycause complexity—one is in contactless payment (using localcommunication technologies such as RFID to trigger payments—use casesare discussed in ETSI TS 102 412), where the payment will need to betied to a clearly identified customer. In such a case, it may bedesirable to identify the mobile phone by the ICCID uniquely associatedwith the physical SIM.

In a detailed example embodiment, the IMSI broker data store may beconfigured as follows:

-   -   1. DS_GT_IMSI_Mapping. DS_IMSI_Pool.    -   2. DS_EF_IMSI_Rules. This DS stores the exact image of the        entire content of the EF file to be downloaded to the SIM via        OTA.    -   3. DS_IMSI_Broker_Event_Log. This DS logs all events from the        IMSI Broker. The log contains for every entry at least the        following information:        -   a. Date/Time        -   b. ResultCode        -   c. GT_(VLR)        -   d. Original IMSI        -   e. New IMSI

DS_GT_IMSI_Mapping This DS stores the IMSI Range to be used for aparticular GT Prefix. This DS has a record structure. GT_PrefixIMSI_Range The first n significant digits of the GT to The IMSI Range tobe used identify the country/network of a VLR. for this GT_Prefix 1 to 6digits 5 to 6 digits EXAMPLE DATA In NL (31) use 20407 (Teleena) IMSIRange. In PT (351) use 23450 (Jersey) IMSI Range. 31 20407 351 23450 3420404 1681 318095 1 23450 2 23450 3 23450 DS_GT_IMSI_Pool This DS storesthe Last_Issued_IMSI of a trusted location-based application(s)TLA IMSIRange. This DS has a record structure. IMSI_Range IMSI_Last_Issued TheIMSI Range to be used. The last IMSI in this range issued to a 5 to 6digits TLA sub. New IMSI are assigned by simply incrementing this valuehowever in the future an IMSI database could be used that allows for therecycling of numbers. 15 digits EXAMPLE DATA 23450 234507891234567 20407204078800000111 20404 204047891212123 318095 318095440000001

In a typical embodiment, The IMSI Broker may perform the followingprocess steps when a new LU message is received from the HLR LogScanner.

ON new LU message containing IMSI and GT_(VLR) received from HLR LogScanner BEGIN LOOKUP GT_Prefix in DS_GT_IMSI_Mapping, using GT_(VLR),returning IMSI_Range. IF first 5 or 6 digits of the IMSI do not matchIMSI_Range BEGIN GET new IMSI (IMSI_New) from DS_IMSI_Pool matchingIMSI_Range (incrementing Last_Used_IMSI) Retrieve IMSI_List from HLR(using LDAP) Provision IMSI_New on HLR using LDAP) Send OTA to addIMSI_New to SIM in EF_IMSI_List Send OTA to replace EF_IMSI_Rules withDS_EF_IMSI_Rules END END

In a typical implementation, the IMSI broker will be able to performmany parallel requests and should be preferably capable of processinghundreds of requests per second.

If there are situations where the range of IMSIs for a given operatorare limited, the IMSI broker may preferably be able to return inactiveIMSIs back to the pool for re-issue to another subscriber at a latertime. This could be achieved by additional OTA messaging to deactivateand/or delete an EF record on a target and/or by indicating that a givenIMSI previously issued to a subscriber and the system HLR is nowinactive or deleted from the HLR.

Call Routing

Optimised call routings connections can be made via any available routesas necessary and appropriate for cost saving and service availability.Calls may be routed through any combination of the followingcommunication networks: Cellular, Landline (PSTN), WiFi, and IP.

For example a ‘Standard’ Low cost call from UK mobile to USA Mobile maybe routed as follows:

-   -   Conventional cellular connection>UK NO>UK service gateway>IP>USA        service gateway>USA NO>Conventional cellular connection.

This uses IP for the long haul from UK to USA so that the total callcost is 2 local connections.

In another example a ‘Near Free’ call from UK to Australia with bothhandsets capable of VoIP over WiFi (VoWiFi) may be routed as follows:

-   -   VoWiFi>UK ISP>IP Routing service>IP>Australian ISP>VoWiFi

In yet another example, a low cost call from Indian mobile to UKlandline may be routed as follows:

-   -   Indian Cellular>Indian NO>Indianservice gateway>IP>Uk service        gateway>UK landline.

A person skilled in the art will appreciate that there are many morecombinations are possible. For example FIGS. 10 and 11 include detailsof signalling for optimised call routing using CAMEL and USSD call backtechniques. A person skilled in the art will appreciate that from thevarious techniques for optimised call routing which are known, thepresent invention is able to operate using these optimum call routingoptions in addition to providing suitable IMSIs and selecting preferrednetworks as discussed below.

A person skilled in the art will appreciate that the method shown inFIG. 10 is an improvement over the system described in WOLFMAN(EP1850625).

Use of this architecture can allow for user preferences to be realisedmore effectively, by allowing the IN of the home network to be used toprovide user preferences and to interpret information from the user. Forexample, the user may not need to customise his or her mobile phonecontacts directory to be internationally independent (by includingnumber in a format such as +14025551212). The IN will have access to theuser's information, and will typically be aware that the user's homelocation will be (say) the UK, and thus that numbers should beinterpreted as being UK numbers with the UK prefix to be added ondialling of these numbers from outside the UK. When using, for example,a CAMEL callback mechanism as shown in FIG. 10, the dialling of a numberby the user without a country prefix may be interpreted by the homenetwork IN as a call to a UK number and the prefix provided accordingly.This could of course apply to any home network location, and notspecifically to the UK.

Preferred Network Management

Networks and handsets work together to ensure continuity of connectionto a network service. However, this may not be the most favourablestrategy for this system and for the user. As described above, a user'smobile phone when travelling near country or region borders, mayinadvertently attach to a foreign network, even though the phone may bephysically located in a home territory. This switch in network may occurif the user's home network's strength falls, meaning that the mobilephone will attempt to connect to another stronger network. In addition,at power-up, mobile phones perform a scan of available networks, anddepending on a set of rules governing network selection, the mobilephone may select the strongest available network, which may not be themost favourable network in terms of call charges.

This problem is illustrated in FIG. 12, which shows two countries 800,802 (although this could be two regions within a country) sharing aborder 804. A first cell tower 806 (base station) provides coverageapproximated by a first circle area 808 for a home network, and a secondsell tower 810 provides coverage approximated by a second circle area812 for a first foreign network. A user subscribed to the home networkat location X, may inadvertently be connected to the foreign network,even though the user has not left their home territory.

Under normal operation, once a mobile phone is attached to a network, itremains attached to it until signal is lost or if the subscribermanually disconnects. As a result, the user may charged high roamingcharges for an extended period even if though they were physically intheir home territory.

According to one aspect of the invention, the mobile phone is able todetermine from the current location a preferred network rather thanmaintaining a ‘status quo’ connection or simply connecting to thenetwork with the strongest signal power. The mobile phone may determinethe preferred network by receiving an OTA message from the user's homenetwork. Alternatively, the mobile phone or SIM within the mobile phonemay be programmed to select a preferred network from the availablenetworks on the basis of network selection rules within the mobilephone/SIM.

This aspect of the invention may be coupled with the IMSI Broker systemsuch that the mobile phone may be arranged to attach, using anappropriate IMSI, to the most favourable network a given area.

In one embodiment, the system (i.e. the user's home network or mobilephone/SIM) is arranged to recognize when a user is in a location where amore favourable connection is available. This is achieved throughmonitoring of network registrations and location updates. The system iscapable of signalling over the air from the host to the mobile phonethat it should detach from the current connection and perform a searchfor a more favourable network.

Location Management and Usage

As described above, the system is configured to be able to identify thecurrent location of the subscriber handset. This current location may beused to perform status updates, SIM data updates and other systemfunctions to optimise the connection and routing of calls. In oneembodiment this is performed by the host system in response to thecurrent location information arriving from the mobile phone. In anotherembodiment, the mobile phone may itself determine from locationinformation stored within the mobile phone/SIM a preferred network, onthe basis of network selection rules stored within the mobile phone/SIM.

Location information can be derived from a plurality of sources. Someexamples are Network Country/Operator ID, GSM (Cellular) Cell ID, WiFiaccess point ID, other fixed radio network location identifiers (CDMA,EVDO, WiMAX for example), GPS and equivalents. The current location maybe cross-checked with database tables containing network coverage forvarious locations. In one embodiment, the location information may berelated to key landmarks, for example airports. In another embodiment,the location information is solely dependent on physical location/mapknowledge. This is because network preferences may be determined ontheoretical preferences, known to the host, even when a subscribed useris currently not picking up a network.

The table of network preferences may be stored on the mobile phone/SIMsand can be modified by the host network as required using the OTAservice.

The ability to determine network preference on the basis of location canbe particularly useful in situations where a user has entered a newpotential service coverage area, but say only WiFi is currentlyavailable. In this case, it would be possible to deploy a new IMSI readyfor use, even before network coverage has been reached.

Forced Reconnection/Rescanning

As described above, the system is capable of instructing the handsetusing OTA signalling under host system control to disconnect from itscurrent connection to a network and to rescan for an optimal connection.

This functionality, is further illustrated in FIG. 12. A user in theirhome country, at location X, should attach to the home network. When theuser travels to location Y, they are still within the coverage area forthe home network, and so should remain attached to the home network.However, when the user travels to location Z, they are outside thecoverage area for the home network, and would initially appear to beroaming in a foreign network. In addition to the IMSI Broker providing alocal IMSI for the new country, the home network is able to determinefrom the current location of the mobile phone which of the availablenetworks is the most preferred network. In FIG. 12, a network coveragearea for a second foreign network 814 is shown by the dashed circle 816.Location Z falls within the coverage areas 812, 816 for both the firstand second foreign networks, and so on the basis of a network preferencelist the home network where the user is registered is able to determinewhich network the user should attach to. If necessary, the mobile phonewill be instructed to detach from a less preferable network beforeattaching to the preferred network. In addition, the IMSI Broker may bearranged to obtain a local IMSI for the preferred network, as opposed toan IMSI that is local to the new territory.

This IMSI Broker server instruction to change IMSIs is referred to as a‘kick’. The benefit of using server initiated IMSI switching is thatmuch more information is known to the server about the current state ofnetworks, costs and the location of the user, than is known to thesoftware running in the SIM. The ability to switch IMSIs under softwarecontrol should be done in conjunction with the understanding that theSIM needs to be able to re-contact the HLR through execution of anemergency reconnect process—such a process will also be needed ifcontact is lost with a network being treated as “home” if there is nophysical network associated with the HLR and the different IMSIs arepeers. To be specific, if a SIM is instructed by the network—kicked—ontoa different IMSI and after a period of time (about 5 minutes) is unableto connect it must rescan all its IMSIs in order to reconnect with theHLR.

When the IMSI has been chosen and has connected to the HLR and the HLRconfirms that this is a reliable link either through an activeacknowledgement or simply no objection being raised after a period oftime then the SIM should signal to the device and other applicationsrunning on the SIM that there has been an a change and otherapplications should behave appropriately. For example upon SIM swap anda period of stability of 3 minutes the SIM could signal to all companionapplications on the SIM that the IMSI is now stable and otherapplications could report information or log into system.

Applications (software) in the SIM and in the device may need to beaware of the IMSI swap process to operate correctly. The SIM shall keeptrack of the IMSI swap process and shall be able to inform applicationson the SIM and the handset of the current status and when a change ofthat status occurs. The SIM may also be inform the user. Applications onthe SIM or device may also be able to query the SIM to find out thestatus of the IMSI selection. A variety of mechanisms may be used forthis status indication, including a specific SIM interface message, aspecific SIM based webservice, a specific use of a SIM toolkit messageor proprietary SIM file. The SIM may decide that the IMSI swap is stablebased on time, a number of specific SIM messages since the lastauthentication following the IMSI change or on a specific message fromthe HLR or network.

A minimum of 4 states shall be held by the SIM; (A) Initialised—thisstate is means that the SIM has not yet determined which network itshould be on. It is typically the state that the SIM is in after poweron or a restart. (B) IMSI Changing—this state means that the SIM hasdetermined that it needs to use a different IMSI and that the IMSIchange process has not yet completed. (C) IMSI Stable—this state meansthat the SIM has determined that it is on the correct IMSI and that theIMSI selection has stabilised. (D) No available service—this state meansthat the SIM has exhausted its rules and has not been able to use anIMSI that will deliver service. As detailed above, the SIM shallrepeatedly attempt to select an IMSI that is valid so it can leave thisstate. The SIM state diagram illustrated in FIG. 17 shows the SIMinitially being in Initialised state (A). If it determines it is on thecorrect IMSI it changes state to IMSI stable (C). If it determines thata SIM swap is required it changes state to IMSI changing (B). From IMSIchanging state (B), once the SIM determines that the device hassuccessfully registered on the correct IMSI and is stable, the SIMchanges to the IMSI stable state (C). If the SIM exhausts all of theIMSIs it can use and cannot register on any of them it changes state toNo Available Service (D) and shall attempt to restart in A after apredetermined time. If the SIM is in state IMSI stable (C) and an eventhappens that requires a change of IMSI (for example changing country)then it shall change state to IMSI changing (B).

In one embodiment, the Intelligent Network comprises a Network LocationManager which monitors network registrations and location updates andcauses handsets to reregister with a more favourable network.

In one embodiment, the mobile phone communicates logistics including aset of available network operators to the IMSI broker to influence theIMSI selection rules. The IMSI broker comprises a rules manager which isarranged to add IMSIs and/or mobile network operators to the availablepool to provide additional choices. In addition, the rules may beupdated in dependence on changes to reciprocal agreements betweennetworks.

In one embodiment, a new IMSI is dynamically assigned to a currentlyattached handset causing is to register with a newly assigned network.

In one embodiment, the network selection and IMSI provisioning may bebased on theoretical network preferences for a given location, withoutrelying on the networks which appear to be available to the mobilephone.

When basing network selection decisions on theoretical networkpreferences, the host may be able to determine that for a given locationX, that networks A, B, and C, are theoretically available. The host mayknow that network C is the preferred network for low cost call routing.However, the mobile phone may only be able to detect/pick-up Networks Aand B. In one embodiment, the host may send an instruction for themobile phone to detach from the current network (could be A or B) andre-scan (at full power) for available networks in an attempt to ensurethat the mobile phone may attach to the preferred network. In thissense, the host is also arranged to ensure that the mobile phone has oris provisioned with an appropriate IMSI for that network, in thatlocation.

In addition, when IMSIs/networks are removed from the IMSI pool/list ofpreferred networks, all currently assigned IMSIs (for those deletednetworks) are invalidated and all SIMs currently registered with thoseIMSIs are caused to reregister with a valid network.

Incoming Call Signalling

Referring to FIGS. 13 and 14, an incoming call from non-subscriber (PSTNshown) is either routed directly to the system HPLMN/HLR or via visitedHLR to home HLR. This ensures that the system always has optimal controlof call routing, CLI presentation and call costs. Depending on thearrangement with visited network, the incoming call may be initiallyrouted direct to the system HPLMN/HLR or to the visited network. If thelatter, then either the signalling is redirected to the system HLR orthe visited HLR looks up the data from the system HLR to determine callrouting and presentation.

Incoming Call Routing

Incoming calls to a subscribed user are preferably made by calling alocal number that the user is known by in the caller's territory;alternatively it is possible for the subscriber to be called by callingany one of the subscribers number from anywhere—although the caller maynot get the best rates in this case.

Additionally, the subscriber may set up additional routing rules—forexample, time based and location-modified time based rules so that thecaller may be optimally routed to the subscriber's phone, his voicemailor another colleague in his office. Where the voicemail is one which isunified across all or some of the user's IMSIs or MSISDNs, it may bedesirable to identify positively with the voicemail which of the user'snumbers was the one actually called. Another use of this rules processorcould be for when the caller may not be aware of the time zone of thesubscriber, so the time based rules can optionally play a messageinforming them of this and whether to continue with a call. FIG. 15 is amap of the world illustrating a method of setting up user preferencerules for incoming call routing on the basis of location, current time,and time-zone. This refers to: (a) local numbers being used to call thesubscriber from different parts of the world as well as (b) time (zoneand time of day) rules.

Outbound calls have a different set of rules: when a subscriber callsone of his contacts, the CLI presentation is such that the contact willpreferably see the subscriber's number not only as one that the contactwill recognise but also as a low-cost number to call back.

In summary, because all call or call signalling is controlled throughthe system HLR/IN, rules controlling call routing and CLI presentationmay be applied to all incoming and outgoing calls so that the system canbe optimised for the best user experience. This approach also allows theuser to determine that different MSISDNs can be treated differently, orbe associated with different service provision. In a conventionalarrangement, supplementary services are enabled or disabled by SIM card,independently of MSISDN or any other factor. Such supplementary servicesmay relate to caller line identification (such as CLIP for presentationof caller line identification and CLIR for restriction of it) but alsomay include services such as call forwarding. For example, a user mayhave two MSISDNs: +14025551212 and +447408800000. The user may specifythat call forwarding and CLIR will be provided for the US number, butnot for the UK number. This can be implemented with the mediation of thehome network IN, which is able to implement actions which will bemediated through the home network or will be able to arrange forappropriate provisioning of the mobile phone logic where implementationat the mobile phone is required.

Machine to Machine Communication

An increasingly important area for mobile communication is in machine tomachine communication in which a communication channel is opened betweenmachines without initiation or direct participation of a person. Usecases include security systems, asset tracking, automated paymentmechanisms, and remote sensing, monitoring and metering (3GPP TS 22.868and ETSI TS 102 412 describe a series of use cases for such technology).As many of these use cases require frequent communication (if typicallywith low overall data transmission volumes), it is very desirable to beable to manage these effectively. The IMSI broker approach describedhere is particularly suitable for such use cases. Further practicalissues associated with effective machine to machine communication arediscussed in 3GPP TS 33.812, which would be considered by the skilledperson in implementing a specific machine to machine solution.

A person skilled in the art, will appreciate that roaming applies to GSMnetworks but also to CDMA, as well as other cellular communicationnetworks. CDMA systems generally do not have a separate SIM module butrather contain all the authentication information within the device. Aperson skilled in the art will appreciate that this invention may beapplied to CDMA systems using the same essential principles but storingmultiple credentials within the device memory.

The examples used for the above illustrations primarily relate to mobilephone roaming. However, a person skilled in the art will appreciate thatthe techniques described herein may be suitable for communicationsrouted through any combination of channels including cellular, WiFi,VoIP, and landline. For example, in some situations (where it is notpossible to provide an IMSI from an FNO which is fully satisfactory forintended purposes, for example), the IMSI Broker may provision an IMSIwhich will allow access to an bearer using SIP so that calls may be madeover networks using internet protocol. In addition, the exampleillustrations herein centre on voice calls. However, the same techniquesapply when users are using their communication devices to accessadditional communication services including connection to voicemail, andconnection to other networks such as Skype and MSN. Similarly, thesetechniques may also be used for data services and text messaging.

Increasingly, users browse the World Wide Web or obtain resources fromthe public internet from their mobile phone. Use of the IMSI broker andhome network IN allow for the user's internet experience to bedetermined by user preferences, rather than by the user's networkconnection status. Typically, web page preferences (for example) will belocalized to a user's network connection (for example, if a user isconnected to a UK network operator, Google will localize togoogle.co.uk) because the local GPRS network will connect to the publicinternet through a GGSN (Gateway GPRS Support Node) associated with thatGPRS network (and consequently with its geographical location). Use ofthe home network IN allows for routing of the connection so as toprovide appropriate localization for the user, and hence correctpreferences.

In order to provide consistency and continuity of service to the user,it may be desirable for the user to use a consistent APN, or set ofAPNs, when accessing data services. To do this, it is necessary to makethese APNs available whatever IMSI the user is currently using. Thiscould be done by making the home set of APNs available to each suchIMSI, or by providing a DNS proxy to a home DNS server and ensuring thatthe HLR grants permission to use the relevant APN or APN set generallyfor that user. A user may thus use many IMSIs while still beingconnected to one or more home APNs for service provision.

In embodiments in which there is no physical network associated with thehome network, then all physical networks have an equal priority. Thismay have practical advantages—for example, it is then not necessary forthe SIM to return to a home network IMSI for any service. Where such ahome IMSI exists, it would be normal to return to this IMSI betweenoutbound calls, which would require a rescan and thus a time when thesubscriber would be unavailable. Where all IMSIs have equal validity,then any can be used for appropriate identification, password provisionetc. for any visited networks. Service selection decisions may be madeto best suit the user—selection may be on the basis of the presentedIMSI, but need not be if another choice would be advantageous.

A person skilled in the art will appreciate that in an alternativeembodiment, the mobile phone may be arranged to request a local IMSIafter determination that a suitable IMSI is not stored within the SIM.The request may be made to the IMSI Broker using OTA services. In thisembodiment, the IMSI Broker would not need to receive notifications fromthe HLR scanner regarding location updates, rather the IMSI broker wouldsimple carry out the steps of obtaining and sending a local IMSI whenrequests are received from mobile devices.

In one embodiment, when a user roams to a new country and is given anIMSI for that country, the user may be offered the choice to add thisnew country to a roaming profile (stored in the user database, which ispointed to from the HLR), so that they may benefit from lower callingand receiving rates. However, the decision regarding the issuance ofIMSIs may be performed independently of any user interaction such thatthe system can ensure lower connection rates for all call routing.

As stated above, one aspect of the present invention keeps track of thesubscribers network identifiers and can switch between practicalidentifiers without loosing track of the primary customer identity. Theprimary customer identity is usually a unique human being (but can be amachine or sometimes a company entity such as a department). Theidentifiers are commonly the customers IMSI (International MobileSubscriber Identity) that resides on a SIM (Subscriber Identity Module)or their telephone number MSISDN (Mobile Subscriber In Number) or otherimportant identities such as MAC address, IP address, email address andIMEI number (Mobile Equipment Identifier). In addition, references toidentity authentication may include a username and password detailsinstead of an IMSI.

As is indicated above, IMSIs and MSISDNs may be swapped when roaming toobtain advantageous pricing. It should be appreciated that other factorsmay be used to determine the most appropriate choice of IMSI. There maybe alternative IMSIs of similar cost which differ in the services thatthey provide or support. Another factor, such as consistency of userexperience, may be more important to a user than price. The following isa list of factors which may be used as well as, or instead of, call costwhen determining which of a set of suitable IMSIs or MSISDNs should beselected in a given situation:

-   -   Handset capability (a handset may be more compatible with one        network than another, or be more effective at particular band        frequencies)    -   Subscription service level (a data only tariff may have a        different selection process from a voice and data tariff)    -   Network reliability    -   Possibility of load sharing on connecting links    -   Reported Quality of Service (may vary with time of day, for        example)    -   (for MSISDNs) To present a consistent identity to a handset,        network or contactless application.

A person skilled in the art will appreciate that IMSIs may be preloadedonto SIMS in many different ways. For example, travel itineraries may beused to preload IMSIs in the handset for the anticipated visited areas.This may be done predictively (for example, if a UK-based user isdetected in Singapore—a travel hub for much of Asia—the user may beprovisioned not only with an IMSI for Singapore but with an entire AsianIMSI set). In addition, an on-line travel company data feed may be usedto optimize IMSI assignment. Also, a user's travel history may be usedto preload new IMSIs into a mobile device. In one embodiment, IMSIs maybe assigned dynamically to a mobile phone if the subscribed user visiteda region more than a predefined number (say 3) of times in the prioryear. These approaches may be used to provide the user with a consistentuser experience in almost every geographical location.

As the IMSI Broker dynamically assigns IMSIs, for a given IMSI for agiven subscriber, additional information is stored as to whether theIMSI is ‘in use’, ‘user active’ ‘system active’, or ‘inactive’. The IMSIBroker is able to track the provisioning of IMSIs, re-using IMSIs asnecessary.

In order to provide consistency and continuity of service to the user,it may be desirable for the user to use a consistent APN, or set ofAPNs, when accessing data services. To do this, it is necessary to makethese APNs available whatever IMSI the user is currently using. Thiscould be done by making the home set of APNs available to each suchIMSI, or by providing a DNS proxy to a home DNS server and ensuring thatthe HLR grants permission to use the relevant APN or APN set generallyfor that user. A user may thus use many IMSIs while still beingconnected to one or more home APNs for service provision.

Five common architectures that allow the handset to use the same APNsare described here and illustrated in FIG. 16:

-   -   1) APN Routing—Roaming hub type 1.    -   In this architecture the handset (A) with a SIM or USIM (B)        communicates via a visited 3GPP network (C) to the visited SGSN        (D). The visited SGSN (D) then communicates with the multi IMSI        aware HLR (F) in the home network environment (G) to determine        whether the APN is allowed and where to route the data for this        APN. In this case the data is routed to a GTP relay (H) in a        roaming hub (I). The roaming hub GTP relay (H) uses a DNS        server (J) to determine where to route the data onwards. This is        typically to a GGSN (K) in the home environment (G). The        GGSN (K) then routes the data to the destination        internet/intranet environment (L).    -   2) APN Routing—Roaming hub type 2.    -   In this architecture the handset (A) with a SIM or USIM (B)        communicates via a visited 3GPP network (C) to the visited SGSN        (D). The visited SGSN (D) then communicates with the multi IMSI        aware HLR (F) in the home network environment (G) to determine        whether the APN is allowed and where to route the data for this        APN. In this case the data is routed to a GGSN (M) in a roaming        hub (I). The roaming hub GGSN (M) uses a DNS server (J) to        determine where to route the data onwards. In this case the        roaming hub GGSN (M) then routes the data to the destination        internet/intranet environment (L).    -   3) APN Routing—National Roaming type 1.

In this architecture the handset (A) with a SIM or USIM (B) communicatesvia a visited national roaming 3GPP network (C) to the visited SGSN (D).The visited SGSN (D) then communicates with the multi IMSI aware HLR (F)in the home network environment (G) to determine whether the APN isallowed and where to route the data for this APN. In this case the datais routed to a GTP relay (N) in the visited network (C). The GTP relay(N) uses a DNS server (O) to determine where to route the data onwards.This is typically to a GGSN (K) in the home environment (G). The GGSN(K) then routes the data to the destination internet/intranetenvironment (L).

-   -   4) APN Routing—National Roaming type 2.    -   In this architecture the handset (A) with a SIM or USIM (B)        communicates via a visited national roaming 3GPP network (C) to        the visited SGSN (D). The visited SGSN (D) then communicates        with the multi IMSI aware HLR (F) in the home network        environment (G) to determine whether the APN is allowed and        where to route the data for this APN. In this case the data is        routed to a GTP relay (P) in the home network (G). The GTP        relay (P) uses a DNS server (Q) to determine where to route the        data onwards. This is typically to a GGSN (K) in the home        environment (G). The GGSN (K) then routes the data to the        destination internet/intranet environment (L).    -   5) APN Routing—Own network.    -   In this architecture the handset (A) with a SIM or USIM (B)        communicates via the home 3GPP network (G) to the SGSN (R). The        home SGSN (R) then communicates with the multi IMSI aware        HLR (F) in the home network environment (G) to determine whether        the APN is allowed and where to route the data for this APN. In        this case the data is routed to a GTP relay (P) in the home        network (G). The GTP relay (P) uses a DNS server (Q) to        determine where to route the data onwards. This is typically to        a GGSN (K) in the home environment (G). The GGSN (K) then routes        the data to the destination internet/intranet environment (L).

In one embodiment, a SIM database as indicated below may be used tostore IMSIs and PLMN data related to the use of the IMSI. This shows howa large quantity of information that controls the search and selectionalgorithm on the SIM can be store in a space-efficient manner. Inconjunction with SIM application software written for this specificdatabase design, the database stores primary search keys and optionalsecondary search keys. The database records also contains otherinformation that is required by the terminal when the record isdetermined optimal for use by the SIM software.

COUNTRY MCC MNC 1 MNC 2 *IMSI *NC 2 2 2 1 1 8 Bytes MCC MCC 1 MCC 2 MCC3 MCC4 0..9 Specific 0 RFU A RFU 1 RFU B RFU 2 RFU C RFU 3 RFU D RFU 4RFU E Wild? 5 RFU F RFU 6 RFU 7 RFU 8 RFU 9 RFU A All - do not search onMNC B RFU C RFU D Get from Network? E RFU F Forbidden? BCD in 4-bit MNCMNC 1 MNC 2 MNC 3 MNC 4 nibbles nibbles 0 . . . 9 Specific 0 HPLMN OPLMNEHPLMN A Pointer to #MNC For specifying H/O/E only. Not for matchinglist B RFU C RFU 1 HPLMN OPLMN EHPLMN D RFU For MCC + MNC matching ANDH/O/E specifying E Wild F Padding If first MNC is all F then followingentry is extra *IMSI Offset into *NC NC file 1 byte Pointer to filecontaining ASCII identifier appended to ‘Truphone’ eg ‘Truphone US orTruphone NZ’ Offset into IMSI *IMSI *IMSI file 1 byte IMSI IMSI SMSc(*)Keys 1 + 8 12 117 or 1 Country MCC MNC 1 MNC 2 *IMSI NC 8 MCC MNC 1MNC 2 *IMSI NC MCC MNC 1 MNC 2 *IMSI NC MCC MNC 1 MNC 2 *IMSI NC MCC MNC1 MNC 2 *IMSI NC MCC MNC 1 MNC 2 *IMSI NC : MCC MNC 1 MNC 2 *IMSI NCIMSI IMSI SMSc (*)Keys 22 IMSI SMSc (*)Keys : : : IMSI SMSc (*)Keys KEYSEncryption Key sets 117 Encryption Key sets : Encryption Key sets NC NC1 NC 2 2 NC 1 NC 2 : : NC 1 NC 2 #MNC MNC 4 : MNC COUNTRY is a proposedrecord structure as shown above where: MCC contains data that the SIMapplication will us to match a country code returned from the handset.MNC optionally contains operator codes data for secondary matchingand/or direct xPLMN data substitution in the EF file. It may alsocontain a reference (pointer) to a secondary list that contains moreentries of similar information *NC is an offset into a Database filecontaining text strings used for network identifier postfixes *IMSI isan offset or pointer into a database file containing a list of IMSIs tobe used for a given record selection IMSI is the IMSI database file KEYSis a database file of network encryption keys referenced by the (*) keysentry in the IMSI database file #MNC is an expansion for the matching oroperational MNC codes used within a country

When the SIM application is triggered to run from either ahandset-originated event or a SIM polling mechanism indicating a changeof connected network may have occurred, the SIM application searchesthough the database for a match based on the country code contained inthe information from the handset or the polling mechanism and may matcha record or optionally, records, in the database. The SIM applicationmay optionally perform secondary matching procedures that can berepeated or nested as required as indicated by the data contained in thesecondary matching records in the database records. If the SIMapplication determines that new operational data is required for correctoperation of the terminal on the currently detected network, the SIMapplication may then read from the SIM database and construct and formatdata structures in preparation for writing said data structures to theSIM primary SIM EF data files.

The SIM EF data files may be written with the new data as determined bythe SIM software at arbitrary points in time or optionally at timesconditioned be but not limited to time of day, geographical location,network conditions or specific signals from the host network.

The operational data contained in the said selected database record mayoptionally contain primary data or links or pointers, optionally nested,to additional operational data contained other SIM database files.

Optionally the embodiment may contain default or fall-through datastores for use in the condition that a match of a specific record is notmade by the SIM algorithm.

The database is flexible to optionally allow matching and selectionbased on but not limited to country, geographical regions consisting ofseveral countries, networks within countries or geographical regions andmay optionally use condition such as but not limited to time, date,geographical information, GPS data, network conditions or specificsignals from the host network.

The data contained in the database may be optionally used fordetermining the PLMN to preferentially connect to, prevent connection toor actively disconnect from PLMNs

The SIM database may optionally be pre-loaded at manufacture, ormodified by OTA information sent from the host system.

The term territory used herein is intended to mean any specificlocality, this may be in terms of countries, regions and possible evenfor given networks.

The terms mobile phone, handset, mobile terminal, communications devicemay be considered as being interchangeable within this document.

A person skilled in the art will appreciate that the present inventionis not limited to details of the described embodiments, rather numerouschanges and modifications may be made without departing from the spiritand scope of the invention as set out in the appended claims.

The invention claimed is:
 1. A method for managing the automaticconnection of a subscribed communication device to a network whileroaming, the method comprising: determining a current location for thesubscribed communication device; retrieving a master list of networksfor that current location, wherein the master list of networks relatesto networks accessible to a plurality of subscriber network identifiersavailable to the subscribed communication device; selecting a preferrednetwork from the master list of networks and a suitable subscribernetwork identifier for the preferred network; and outputting aninstruction for the subscribed mobile device to connect to the preferrednetwork using the suitable subscriber network identifier; wherein theselecting step for the suitable subscriber network identifier comprises,at a central server receiving notification relating to a change in acurrent location for the subscribed communication device, determiningfrom the notification whether a new subscriber network identifier is tobe provisioned from the central server, and if so selecting a subscribernetwork identifier on the basis of the preferred network and the currentlocation and outputting the selected subscriber network identifier tothe subscribed communication device.
 2. The method of claim 1, furthercomprising monitoring location updates for the subscribed communicationdevice; determining if current network is preferred network, on thebasis of network selection rules.
 3. The method of claim 2, furthercomprising instructing the subscribed communication device to disconnectfrom current network if determined to be not the preferred network;instructing the subscribed communication device to reconnect to thepreferred network.
 4. The method of claim 1, wherein the determiningstep comprises determining the current location on the basis of thephysical location of the subscribed communication device as determinedusing global positioning systems.
 5. The method of claim 1, wherein thedetermining step comprises determining the current location on the basisof the one or more of the group comprising: Network Country/Operator ID;GSM (Cellular) Cell ID; WiFi access point ID; and other fixed radionetwork location identifiers.
 6. The method of claim 1, wherein theselecting step comprises selecting a preferred theoretical network fromthe master list of networks known to be available in a certain localityof the current location.
 7. The method of claim 1, wherein the selectingstep comprises selecting a preferred network on the basis of thenetworks which the subscribed communication device determines arecurrently available.
 8. The method of claim 1, wherein the method iscarried out on the subscribed communication device, the method furthercomprising receiving an updated master list of networks from the centralserver.